The present invention relates to an automatic cooking apparatus including a storage and transfer device for storing and transferring a foodstuff, for example, an apparatus for cooking tacos automatically.
The operation of a conventional automatic cooking apparatus is summarized below with reference to an automatic taco cooking apparatus.
(1) Summary of the cooking operations
FIG. 3 is a schematic view showing the cooking operations of an automatic taco cooking apparatus.
To cook a taco, a tortilla (used as a soft wrapper for the taco) is transferred from a tortilla storage and transfer device 7 and placed onto a conveyor moving toward right in the figure. A taco being cooked on the conveyor is sequentially moved to the transfer position for each storage and transfer device for supplying a foodstuff required for cooking, and the corresponding foodstuff is then supplied from each storage and transfer device. For the tacos shown in the figure, sequentially supplied foodstuffs include minced or ground meat from a minced meat storage and transfer device 10, lettuce from a lettuce storage and transfer device 13, cheese from a cheese storage and transfer device 14, and tomatoes from a tomato storage and transfer device 15. The taco thus cooked is obtained from the right end of the figure as commodities.
Taco shells are stored in a taco shell storage and transfer device 9, and sour cream is stored in a sour cream storage and transfer device 12.
The conveyer does not always move, but rather moves for each foodstuff supply so that tacos can be transferred and stopped at the foodstuff transfer position of each storage and transfer device. When the taco is transferred to the transfer position, the corresponding foodstuff is supplied to the taco.
In addition, the cooking operations, such as moving the conveyor and transferring a foodstuff from the storage and transfer device, are executed by a master control section which controls the overall automatic taco cooking apparatus.
(2) Operations of foodstuff storage and transfer devices
The operations of the foodstuff storage and transfer devices are described with reference to the cheese storage and transfer device.
FIG. 4 schematically shows the operations of the cheese storage and transfer device. FIG. 4 provides not only a conventional example but also one embodiment of the present invention.
The cheese storage and transfer device comprises a storage and transfer section 300a for storing a foodstuff to be transferred, i.e. cheese, a spiral screw 304 for transferring cheese, a refill section 300b for preserving cheese for refilling, and rollers 301 for transferring cheese from the refill section 300b to the storage and transfer section 300a. The spiral screw 304 and the rollers 301 are driven by a motor (not shown).
In addition, to detect whether the storage and transfer section 300a contains a predetermined amount of cheese or not, for example, a foodstuff sensor light emitting section 302 for emitting infrared rays and a foodstuff sensor light receiving section 303 for receiving those infrared rays are installed opposite to each other across cheese in the storage and transfer section 300a.
The motor (not shown) for driving the rollers 301 and the spiral screw 304, the foodstuff sensor light emitting section 302, and the foodstuff sensor light receiving section 303 are connected to the storage and transfer control section. The storage and transfer control section is in turn connected to the master control section described above.
Typically, as described above, when the conveyor moves to transfer a taco being cooked to a position under the spiral screw 304 for transferring cheese, the corresponding foodstuff is transferred. At the same time, when the storage and transfer control section detects, from the foodstuff sensor light receiving section 303, that an amount of cheese stored in the storage and transfer section 300a is less than a predetermined amount, it immediately drives the rollers 301 to refill cheese. Upon detecting that the amount of cheese in the storage and transfer section 300a has reached the predetermined amount via the foodstuff sensor light receiving section 303, the storage and transfer control section stops the driving of the rollers 301, thus completing the refilling operation.
The above conventional automatic cooking apparatus has the following problems.
When the foodstuff sensor light receiving section 303 detects an insufficient quantity of a foodstuff, the rollers 301 immediately operate to refill the foodstuff. That is, the timing for starting the foodstuff refilling operation depends on detection by the foodstuff sensor light receiving section 303, and is not linked with other conditions, such as the position of the taco being moved or waiting on the conveyor, the timing of foodstuff transfer, or other conditions of the cooking apparatus (for example, the opening or closing doors of the chambers of the apparatus). Accordingly, the following inconveniences and action must be considered.
For example, during the transfer of cheese, in case the quantity of the foodstuff becomes insufficient, refilling of the foodstuff is immediately started. Thus, to avoid taco with the insufficient foodstuff, the foodstuff transfer must be once stopped and restarted after refilling is completed. That is, the transfer operation must be restarted after the foodstuff transfer time corresponding to the insufficiency of the foodstuff has been calculated.
Assuming that the conveyor is stopped to await an instruction for supplying the next foodstuff into the taco, in case the amount of cheese in the cheese storage and transfer section 300a becomes less than a predetermined amount, the storage and transfer control section detects this condition from a signal received from the foodstuff sensor light receiving section 303 and drives the rollers 301 to begin refilling. At this moment, if a transfer door for another storage and transfer device is opened to refill the required quantity of the foodstuff, it is necessary to generate an alarm indicating an abnormal condition to avoid danger.
As described above, conventional foodstuff refilling is immediately started simply based on a signal received from the foodstuff sensor light receiving section indicating whether the predetermined amount of foodstuff is present or not, and this operation is not necessarily linked with the operations of the entire apparatus. Consequently, the apparatus must be designed by taking its various operational conditions into consideration, and thereby results in need for a substantial amount of time and labor as well as complicated apparatus control operations.
Furthermore, as described above, since it is not detected prior to transferring of the foodstuff whether the amount of a foodstuff will be insufficient or not during transferring of the foodstuff, this amount must be constantly monitored even during refilling of the foodstuff. As a result, whenever cheese passes through the foodstuff sensor light emitting section and the light receiving section while refilling cheese, the foodstuff sensor light receiving section repeats a signal indicating the sufficiency and a signal indicating the insufficiency of cheese, so that the motor drive section is repeatedly instructed for driving and stopping the rollers 301. The motor drive section, however, can not follow such instructions, and accordingly, the roller drive section fails to operate properly.
It is an objective of the present invention to provide an automatic cooking apparatus that can be designed easily and which can operate reliably.